Designing a Road Network Using John Rawls’s Social Justice Approach

Abstract

Financial resources for road network developments are commonly distributed in such a way that wealthy regions gain more benefit, which would gradually intensify the socioeconomic gap among regions. By presenting a short introduction to John Rawls’s theory of justice, this study proposes an equitable road network design model. Based on John Rawls’s theory of justice, the model focuses on maximizing the accessibility of those regions that are considered poor in terms of the current status of their accessibility. The model, formulated as a bilevel integer optimization problem, tries to establish a more equitable distribution of accessibility among various regions by allocating a limited budget to the candidate links of network development. As a case study on the real data of an interprovincial network in Iran, results indicate that the ratio of the population of groups with low and relatively low accessibility to the total population of the country has been reduced from 30% in the initial situation to 11%. Additionally, the min-to-max ratio of accessibility has increased from 3.09% to 14.39% in the current status since this theory is based on the maximization of benefits for the poorest groups in society.